The present ages of the three persons are in the proportion 4 : 7 : 9. Eight years ago, the sum of their ages was 56 years. The present age of the eldest person is?
Note
A: B: C = 4: 7: 9 and
(A + B + C) = 56 + (8 + 8 + 8) = 80.
∴ C's age = (80 × 9/20) years = 36 years.